Zero Escape Wiki

The Planet Keys are a group of keys marked with the astrological symbols of planets that are used on their respective locks. The exceptions to this group are the Sun Key and the Zero Keycard, which although are not planets, are counted towards this group anyway for continuity purposes. The keys can take the form of either a physical key or that of a keycard. These keys are found in Zero Escape: Nine Hours, Nine Persons, Nine Doors inside various escape rooms.

Sun Key

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The Sun Key is found in a pipe in the Torture room.

The door needed to open with the Sun Key is found on C Deck near the central staircase. It leads to the Storage room.

Mercury Keycard

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This key is found in the Shower room inside the drain.

It is used to open the door and to activate the C Deck elevator near the large hospital room. The elevator leads to the Bottom Deck and Door 2.

Venus Key

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This key is found in the Casino. Junpei finds it in the middle slot machine's drawer.

The lock is found in the gate near the Casino.

Earth Key

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This key is found in the Laboratory inside one of the lockers.

The Earth door is found on A Deck near the central staircase. It leads to Door 1 and the chart room.

Mars Key

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This key is found in the 2nd class cabin behind the dog painting.

The lock is in the same area outside the cabins.

Jupiter Key

Oproom jupiterkey.png

This key is found in the Operating room in a drawer on John's scale.

The lock is in the C Deck hallway. It leads back to the central staircase.

Saturn Keycard

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This key is found in the Kitchen inside the oven.

It opens the exit of the Kitchen. It is also used to activate the elevator on C Deck behind the staircase. The elevator leads to E Deck and Door 6.

Uranus Keycard

Caphead uranus card.png

This card is found in the All-ice file, located in the Captain's quarters. Says BOTTOM DECK LIBRARY on the lower right corner.

The card reader is next to the library on the Bottom Deck, and opens the door to it.

Neptune Key

Work neptunekey coffinshield.png

This key is found in the Study, inside the coffin.

The lock is found on the Bottom Deck and leads to the Incinerator.

0 Key Card

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The card found in the Study, inside a drawer along with a photograph.

The lock is in the same room and opens the exit to the study.


  • The Sun Key is the only key that is never used by Junpei, as the Sun Door is already unlocked.
  • As Pluto was declared a dwarf planet in 2006, no Pluto Key is found in the game.
v · e · d Zero Escape: Nine Hours, Nine Persons, Nine Doors (series spoilers within)
Main focus: Second Nonary Game
Main characters (players) Junpei (playable) · Ace · Snake · Santa · Clover · Akane Kurashiki · Seven · Lotus · Ninth man
Other characters Zero (game host) · Alice · Funyarinpa · "Cap" · "Guy X" · Science Boy
Mentioned characters All-ice · Dashiell Gordain · Ennea and Nona Kashiwabara · Ichiro · Kurashiki parents
Doors & Escape Rooms 3rd class cabin · Door 1 (Chart room and Captain's Quarters) · Door 2 (Confinement room and Torture room) · Door 3 (Shower room) · Door 4 (2nd class cabin and Kitchen) · Door 5 (1st class cabin and Casino) · Door 6 (Steam engine room and Cargo room) · Door 7 (Operating room) · Door 8 (Laboratory) · Small Door 9 (Library, Study, Incinerator) · Large Door 9 (Incinerator) · Door q (exit)
Other locations Building Q (main location) · Junpei's apartment · Central Staircase · Chapel · Earth · Elevator · Gigantic · Large hospital room · Nevada · Storage
Game mechanics Bracelet · Calculator · Digital root · Numbered Doors · Planet Keys · RED and DEAD
Terms Bootstrap paradox · Cradle Pharmaceutical · Crash Keys · Esper · First Nonary Game · FLOW Chart · Free the Soul · Ganzfeld Experiment · Luminol · Map · Morphogenetic field · Nonary Game · Soporil
Archives Answers · Files · Endings · Mistakes · Trophies · Timeline